The present invention relates to flexible and pivotable razor cartridges and associated assemblies.
In recognition of the fact that surfaces to be shaved are not perfectly planar, razor cartridges have been designed to flex during shaving. In order to maximize the flexibility of the cartridges, including associated blades, various designs have been developed. For example, one advantageous design is disclosed in U.S. Pat. No. 5,475,923 where a segmented guard bar is utilized. That design has proven to be very successful in providing overall flexibility to the razor cartridge without noticeable distortion to the blade geometry during shaving.
The consistent achievement of a close, safe and comfortable shave depends upon careful control of the blade geometry. While prior art designs including the design discussed above in connection with the ""923 patent have been acceptable, a need continues to exist for a razor cartridge with improved flexibility.
The present invention overcomes the drawbacks of the prior art by providing a razor cartridge which may include one or more blades which utilizes flexible beams to provide enhanced flexibility.
In an effort to increase comfort and shaving efficiency, many shaving razor assembly designs having pivotable razor cartridges have been developed. However, existing pivotable cartridges do not have the ability to flex.
Notwithstanding these prior art designs, a need for pivotable razor assembly designs having improved features such as enhanced flexibility, stability, smoothness in operation and the like continues to exist.
The present invention overcomes the drawbacks in the prior art by providing a razor cartridge and associated razor assembly which is both pivotable and flexible. The present invention also overcomes drawbacks associated with the prior art by providing a razor cartridge which can flex through a neutral plane of an associated shaving aid so as to prolong the life thereof.
In accordance with one aspect of the present invention, a razor cartridge is provided which comprises a frame having a front section and a rear section, a cap arranged at the rear section and a guard bar arranged at the front section. A shaving aid may be arranged on the cap and may extend longitudinally along a neutral plane. The cartridge comprises at least one blade supported on the frame that is movable along with the frame upon application of a force encountered during shaving between an at rest position where the at least one blade has a substantially planar configuration and a flexed position where the frame flexes through the neutral plane and where the at least one blade is in a substantially concave or convex configuration with respect to the top surface thereof.
Preferably, the shaving aid comprises a polymer strip. The expected useful life of such strip may be prolonged by flexing of the associated cartridge through the neutral plane.
It is also preferable for the frame and the at least one blade to be constructed and arranged so that the blade can slide longitudinally within a limited range upon movement between the at rest and flexed positions.
In another preferred embodiment, the razor cartridge may comprise one or more flexible beams for facilitating the return of the at least one blade and frame from the flexed position to the at rest position. In this embodiment, the flexible beams may be constructed and arranged to stretch into tension or shrink into compression when deformed to a flexed position.
In order to facilitate securing of the at least one blade to the frame, a pin may be utilized to secure a central portion of the blade to the frame. The frame may comprise first and second opposing end walls having slots therein. The at least one blade may extend longitudinally between the first and second end walls and may be arranged within the slots thereof. In a preferred embodiment, ample space exists to accommodate limited longitudinal sliding of the at least one blade within the slots during flexing thereof.
In another aspect of the present invention, a razor assembly is provided which comprises the razor cartridge as described above in combination with a handle assembly.
In accordance with yet another aspect of the present invention, a razor assembly is provided which comprises a handle assembly and a razor cartridge attached to the handle assembly for pivotal movement between a rear position and a forward position upon application of a force exerted on the razor cartridge during shaving. In accordance with this aspect of the present invention, the razor cartridge may be initially biased to any one of various positions such as its rear most position, forward most position or a central position.
The razor cartridge includes a frame, a fixed length elongated cap forming the upper part of the frame, at least one blade supported on the frame, which blade extends longitudinally along the frame, and at least one flexible spring beam forming a lower part of the frame. The cap, the at least one blade, and the at least one spring beam are movable upon application of a downward force on the cartridge during shaving from at rest positions where they are in substantially planar configurations to flexed positions where they are in substantially concave or convex configurations with respect to their top surfaces.
Preferably, the razor assembly further comprises pivot biasing means for biasing the razor cartridge to its rear position. The pivot biasing means may comprise an elongate spring arm extending upwardly from the handle assembly and having a free end arranged in contact with the razor cartridge whereby the razor cartridge is urged rearwardly.
The inclusion of the flexible spring beams as part of the razor cartridge frame facilitates the at least one blade and the frame itself to return from their flexed positions to their rest positions. The at least one flexible spring beam may be secured to the remainder of the frame below the bottom surface of the at least one blade and may extend longitudinally therewith.
The above features and advantages of the present invention will be more fully understood with reference to the following detailed description when taken in conjunction with the accompanying drawings.